EP1342496B1 - Spark-ignited internal combustion engine with an NOx-adsorber - Google Patents

Spark-ignited internal combustion engine with an NOx-adsorber Download PDF

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Publication number
EP1342496B1
EP1342496B1 EP03008344A EP03008344A EP1342496B1 EP 1342496 B1 EP1342496 B1 EP 1342496B1 EP 03008344 A EP03008344 A EP 03008344A EP 03008344 A EP03008344 A EP 03008344A EP 1342496 B1 EP1342496 B1 EP 1342496B1
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EP
European Patent Office
Prior art keywords
absorption layer
internal combustion
combustion engine
engine according
exhaust
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP03008344A
Other languages
German (de)
French (fr)
Other versions
EP1342496A2 (en
EP1342496A3 (en
Inventor
Wolfgang Held
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Volkswagen AG
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Volkswagen AG
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Filing date
Publication date
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Publication of EP1342496A2 publication Critical patent/EP1342496A2/en
Publication of EP1342496A3 publication Critical patent/EP1342496A3/en
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Publication of EP1342496B1 publication Critical patent/EP1342496B1/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9495—Controlling the catalytic process
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
    • B01D53/04—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography with stationary adsorbents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
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    • B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
    • B01D53/04—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography with stationary adsorbents
    • B01D53/0407—Constructional details of adsorbing systems
    • B01D53/0415—Beds in cartridges
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    • B01D—SEPARATION
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    • B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
    • B01D53/04—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography with stationary adsorbents
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    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9481—Catalyst preceded by an adsorption device without catalytic function for temporary storage of contaminants, e.g. during cold start
    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9481—Catalyst preceded by an adsorption device without catalytic function for temporary storage of contaminants, e.g. during cold start
    • B01D53/949—Catalyst preceded by an adsorption device without catalytic function for temporary storage of contaminants, e.g. during cold start for storing sulfur oxides
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    • F01N3/0828—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents characterised by the absorbed or adsorbed substances
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    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
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    • F01N3/0871—Regulation of absorbents or adsorbents, e.g. purging
    • F01N3/0885—Regeneration of deteriorated absorbents or adsorbents, e.g. desulfurization of NOx traps
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    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/22—Control of additional air supply only, e.g. using by-passes or variable air pump drives
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    • F01N2250/12—Combinations of different methods of purification absorption or adsorption, and catalytic conversion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2570/00—Exhaust treating apparatus eliminating, absorbing or adsorbing specific elements or compounds
    • F01N2570/04—Sulfur or sulfur oxides
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/03—Adding substances to exhaust gases the substance being hydrocarbons, e.g. engine fuel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B1/00—Engines characterised by fuel-air mixture compression
    • F02B1/02—Engines characterised by fuel-air mixture compression with positive ignition
    • F02B1/04—Engines characterised by fuel-air mixture compression with positive ignition with fuel-air mixture admission into cylinder
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B75/00—Other engines
    • F02B75/12—Other methods of operation
    • F02B2075/125—Direct injection in the combustion chamber for spark ignition engines, i.e. not in pre-combustion chamber
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
    • F02B23/08—Other engines characterised by special shape or construction of combustion chambers to improve operation with positive ignition
    • F02B23/10—Other engines characterised by special shape or construction of combustion chambers to improve operation with positive ignition with separate admission of air and fuel into cylinder
    • F02B23/101—Other engines characterised by special shape or construction of combustion chambers to improve operation with positive ignition with separate admission of air and fuel into cylinder the injector being placed on or close to the cylinder centre axis, e.g. with mixture formation using spray guided concepts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2200/00—Input parameters for engine control
    • F02D2200/02—Input parameters for engine control the parameters being related to the engine
    • F02D2200/08—Exhaust gas treatment apparatus parameters
    • F02D2200/0802—Temperature of the exhaust gas treatment apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/021—Introducing corrections for particular conditions exterior to the engine
    • F02D41/0235—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus
    • F02D41/024—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to increase temperature of the exhaust gas treating apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/14—Introducing closed-loop corrections
    • F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
    • F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
    • F02D41/1454—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an oxygen content or concentration or the air-fuel ratio
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Definitions

  • the invention relates to a spark-ignited internal combustion engine or diesel internal combustion engine according to the preamble of patent claim 1 and to a method for controlling an absorber arranged in an exhaust line of a spark-ignited internal combustion engine or a diesel internal combustion engine.
  • Such a storage catalyst is described in detail in EP 0 580 389 A for use in motor vehicles, high temperatures (over 500 ° C.) being necessary for the regeneration of the absorber.
  • high temperatures over 500 ° C.
  • the use of the storage catalyst is only possible in motor vehicles that have a high exhaust gas temperature, d. H. especially in motor vehicles with a gasoline engine.
  • the use is only partially possible here, since under certain operating conditions of the internal combustion engine, such as those given in city traffic, the acceleration phases high nitrogen oxide emissions occurs, but not a long-lasting high temperature is achieved for the regeneration of the absorber, especially of sulfur oxides, is required.
  • the object of the invention is to provide a suitable for use with diesel engines or direct injection gasoline engines absorber for nitrogen oxides and a corresponding method available with which a regeneration of the absorber should be possible even at low exhaust gas temperatures.
  • the usual absorbent materials can be used, as described, for example, in US Pat. No. 4,755,499, but also in EP 0 580 389 A or WO 94-04258. All these storage materials have in common that they have an elevated working temperature, in particular during regeneration (especially when removing the sulfur oxides) an even higher temperature is required. For most storage media of this type, temperatures in the range of 150 ° C to 700 ° C, especially temperatures above 300 ° C are needed. Such temperatures usually occur in motor vehicles with gasoline engines, but are relatively rare in diesel vehicles and especially in direct-injection internal combustion engines.
  • the preferred NOx storage materials are thus distinguished by the fact that they can store nitrogen oxides under net oxidizing conditions (stoichiometric excess of oxidizing agents), as present in the exhaust gas of lean-burn engines, and reduce them while reducing the oxygen excess.
  • the NOx storage catalysts are usually also noble metal coated, in particular with the usual noble metal coatings for three-way catalysts.
  • the regeneration of the NOx-laden storage material is then advantageously at ⁇ ⁇ 1 in a regeneration phase.
  • the course of the reactions depends inter alia on the temperature of the catalyst, but also on the concentration of the reactants at the active center of the catalyst and the flow rate of the gas.
  • absorbers are particularly suitable with a carrier body made of metal foil.
  • the channels that are coated with the absorption layer make different, so that, for example, a turbulence (turbulent flow) of the exhaust stream is selectively adjustable in the channels.
  • the absorber carrier body with different channel sections are used, wherein z. B. a central region of the channels to achieve a turbulent flow is changed. This is possible, for example, by changing the channel cross-section or by twisting or twisting the channels. As a result, the carrier body can be adjusted specifically for particularly favorable reaction conditions along the flow channels.
  • Another special feature of the carrier body is in addition to the possible different number of channels in the flow direction and the introduction of cross-sectional changes along the flow direction and the segmentation of the carrier body, wherein z. B. a segment with absorption layer near the motor outlet and another segment with absorption layer is arranged slightly more remote. As a result, good NOx cleaning values can be achieved even in fuel-optimized engines, even under very different driving conditions.
  • the NO x storage has particularly good absorption and desorption characteristics when the flow passages for the exhaust gas are swirled in a central region to achieve a turbulent flow, whereas the inlet region and the outlet region do not particularly favor this turbulent flow Have structure.
  • the simplest means of producing such a turbulent flow is, for example, a transition from a large to a small one Diameter in the channels, but also a rotation of the entire body in this area is suitable for generating the turbulence.
  • the particularly favorable properties are presumably achieved by a separation of the individual reaction steps for the reduction of nitrogen oxides to individual segments of the carrier body, wherein the changed middle range guarantees better reaction conditions compared to the unchanged middle range.
  • the absorption layer has an increased surface area of at least 20 m 2 / g, in particular at least 40 m 2 / g.
  • the absorption layer preferably has a pore volume of at least 0.2 cm 3 / g and in particular at least 0.4 cm 3 / g, wherein a bimodal pore size distribution is also suitable with micropores and macropores. This is achieved, for example, by the choice of a specific particle size for the formation of the absorber surface, wherein mixtures or specific distributions of different particle sizes are also suitable.
  • the absorption surface is in particular ⁇ -alumina, which is loaded with one or more elements from the group of alkali metals, alkaline earth metals, rare earths and / or lanthanum. Copper and manganese are also suitable elements.
  • the elements are usually present as oxide, but also as carbonate or nitrate, wherein the storage effect is achieved by forming corresponding nitrates and sulfates, which are then converted under the appropriate reaction conditions again to oxides or carbonates. This makes it possible to absorb NOx and / or SOx in particular from an exhaust gas containing at least 1% oxygen.
  • the absorbed substances are released in particular by increased temperatures and in a reducing atmosphere.
  • the oxygen concentration is determined in the exhaust gas, in which case the oxygen concentration or a quantity in known relationship with the oxygen concentration can be used to control the absorption or desorption process.
  • the temperature of the exhaust gas stream wherein the temperature of the absorption layer is decisive, which is determined directly or indirectly.
  • the temperature can be measured for example by measuring the temperature of the exhaust stream or the carrier body; It is also possible to determine the temperature via a characteristic map of the internal combustion engine.
  • absorption layers in a thickness of at least 50 ⁇ m, in particular at least 70 ⁇ m and particularly advantageously at least 90 ⁇ m (average layer thickness of a cross section, values apply to ceramics, in the case of metal the half values apply), whereby this layer thickness of the absorption layer preferably over at least 50% and in particular at least 80% of the absorber extends.
  • Such layer thicknesses allow a higher storage capacity compared with the conventional absorbers and thus the longer intervals described above until regeneration.
  • the regeneration can advantageously take place when the operating conditions of the internal combustion engine cause a correspondingly high temperature of the exhaust gas stream and thus of the absorption layer.
  • an additional heating of the absorption layer is provided, which takes place via the mixture formation.
  • Preferred heating measures are ignition measures, changing the ⁇ , lowering the ⁇ to ⁇ 1 and Senkundär Kunststoffzugabe for generating exothermic oxidation of an oxidation catalyst or via an ignition device.
  • Particularly advantageous here again is a segmented absorber, which is then heated reaction-specific. Thus, for example, only a downstream arranged absorber area can be heated, especially with a significant spatial separation of Absorbersegmente (see above) ..
  • By the arrangement of individual segments for individual reactions at different distances to the exhaust valve in the engine and motor remote position can also be a thermal aging of the absorber reduce (in addition to the advantage of particularly favorable reaction temperatures in individual absorber areas).
  • the method uses the measures described above in the absorber and in the embodiment, as well as the features described in the method and in the embodiment can be used in the absorber described above.
  • the drawing shows the absorber in an exhaust system of an internal combustion engine (gasoline engine).
  • An absorber 1 is seated in an exhaust line 2 of a spark-ignited internal combustion engine 3 with direct fuel injection, whose operation is controlled by an engine management system.
  • the engine management 4 acts on an injection pump 5, which conveys fuel from a tank 6 (not shown) to an injection nozzle 7.
  • the spark plug 18 and the ignition of the fuel-air mixture in the cylinder wherein the ignition coil is not shown.
  • the most diverse leading to the engine management 4 common supply and discharge lines are not shown.
  • a three-way catalyst 8 is arranged downstream of the absorber 1 in the exhaust line 2, and an arrangement of the three-way catalyst 8 upstream of the absorber 1 is also possible.
  • the absorber 1 is composed of two metal foils, one of which is corrugated with a smooth foil (soldered to the wave crests). By rolling this multilayer film to obtain a cylindrical body having a plurality of axially extending channels in it. Furthermore, the carrier body of the absorber was rotated in a central region 15 about its longitudinal axis, so that here the individual channels 16th narrowed and tortuous. A similarly acting turbulence-forming structure can also be achieved with a transverse undulation in one or both of the metal foils.
  • the metal foil contains a few percent of aluminum and is oxidized so that a washcoat containing ⁇ -aluminum oxide adheres better to the metal foil.
  • the Aluminiumoxidwashcoat also contains the elements sodium, barium, cerium and lanthanum, which are grown as salts (nitrates, oxides, hydroxides) on the alumina.
  • the absorber is obtained.
  • the absorber is impregnated with a platinum and rhodium-containing solution (in addition to or instead of rhodium, the solution may also contain palladium), from which then the corresponding precious metals are released as such.
  • This noble metal coating corresponds to a three-way catalyst coating.
  • the absorber thus obtained is electrically contacted and inserted into a housing so that a current flow through it to ground (the housing) is possible.
  • the electrical contact 9 is connected at the other end to the controller 4.
  • a temperature sensor 10 is used in the carrier body, which also leads to the controller 4.
  • a broadband lambda probe 11 is inserted into the exhaust pipe, which in turn passes on its values proportional to the oxygen concentration present in the exhaust gas flow to the controller 4.
  • a fuel injection 12 is provided upstream of the lambda probe 11, which is supplied in accordance with control commands from the controller 4 with fuel.
  • an air injector 13 is provided which receives air from a pump 14 controlled by the controller 4.
  • the internal combustion engine 3 is of a direct injection gasoline engine type whose exhaust gas flow normally has a high oxygen excess and a temperature around 200 ° C to 500 ° C.
  • nitrogen oxides present in the exhaust gas and oxides of sulfur are incorporated in the absorption layer of the absorber 1, with any oxidizable constituents (usually hydrocarbons) being oxidized at the same time by the noble metal coating of the absorber 1.
  • the absorber Upon reaching the saturation limit or at predetermined time intervals (and others Control variables are possible, such as a NOx determination in the exhaust gas after the absorber) is the absorber to regenerate ie to free from the embedded example as barium nitrate NOx.
  • barium sulfate embedded oxides of sulfur can be removed in this case.
  • it is checked by the control unit 4 via the temperature sensor 10, whether the temperature of the absorber coating for a regeneration is high enough. If the temperature is below 500 ° C, fuel is injected via the fuel injection 12 into the exhaust gas stream, which catalytically burns with the oxygen present in the exhaust gas stream at the noble metal coating of the absorber 1, thereby increasing its temperature.
  • a rich mixture is set in the exhaust, d. H. continue to inject fuel (over 12) and / or by injecting a rich mixture into the cylinder.
  • a throttle 17 is advantageously closed via the controller 4 in the intake passage 16 of the internal combustion engine 3, so that less air enters the internal combustion engine 3. This reduces the proportion of oxygen in the exhaust gas flow in such a way that the NOx and SOx are released from the absorption layer and the NOx is also reduced immediately.
  • the end of the regeneration can be time-controlled but can also be controlled, for example, via the exothermic nature of the reaction temperature.
  • the regeneration as described in DE 43 42 062 A, take place, d. H. the exhaust gas stream is throttled before the absorber and in particular passed into a bypass to the absorber.
  • the Lufteindüsung 13 is provided, which is set during the fuel injection (about 12) or the operation of the internal combustion engine with a rich mixture of the controller 4 in operation. As a result, any remaining hydrocarbons are oxidized in the downstream catalyst 8 to carbon dioxide and water.
  • the fuel injection 12 can be dispensed with, since a sufficient enrichment of the exhaust gas flow can be achieved without difficulty via the fuel injection 7 into the combustion chamber of the internal combustion engine.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Environmental & Geological Engineering (AREA)
  • Toxicology (AREA)
  • Materials Engineering (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Description

Die Erfindung betrifft eine fremdgezündete Brennkraftmaschine oder Dieselbrennkraftmaschine gemäß dem Oberbegriff des Patentanspruchs 1 sowie ein Verfahren zur Steuerung eines in einem Abgasstrang einer fremdgezündeten Brennkraftmaschine oder einer Dieselbrennkraftmaschine angeordneten Absorbers.The invention relates to a spark-ignited internal combustion engine or diesel internal combustion engine according to the preamble of patent claim 1 and to a method for controlling an absorber arranged in an exhaust line of a spark-ignited internal combustion engine or a diesel internal combustion engine.

Aus der US 4,755,499 ist die reversible Speicherung von Stickoxiden und Schwefeloxiden z. B. aus Abgasen von Kraftfahrzeugen bekannt, wobei der Absorber durch Erhitzen in einer reduzierenden Atmosphäre regeneriert wird. Hierbei tritt gleichzeitig eine Reduktion der Stickoxide ein.From US 4,755,499, the reversible storage of nitrogen oxides and sulfur oxides z. B. from exhaust gases of motor vehicles, wherein the absorber is regenerated by heating in a reducing atmosphere. At the same time, a reduction of the nitrogen oxides occurs.

Ein solcher Speicherkatalysator ist in der EP 0 580 389 A für den Einsatz bei Kraftfahrzeugen näher beschrieben, wobei auch hier hohe Temperaturen (über 500 °C) für die Regeneration des Absorbers notwendig sind. Hierdurch ist der Einsatz des Speicherkatalysators nur bei Kraftfahrzeugen möglich, die eine hohe Abgastemperatur haben, d. h. insbesondere bei Kraftfahrzeugen mit einem Otto-Motor. Jedoch ist auch hier der Einsatz nur bedingt möglich, da unter bestimmten Betriebsbedingungen der Verbrennungskraftmaschine, wie sie beispielsweise im Stadtverkehr gegeben sind, durch die Beschleunigungsphasen ein hoher Stickoxidausstoß erfolgt, nicht jedoch lang anhaltend eine hohe Temperatur erreicht wird, die für die Regeneration des Absorbers, insbesondere von Schwefeloxiden, erforderlich ist.Such a storage catalyst is described in detail in EP 0 580 389 A for use in motor vehicles, high temperatures (over 500 ° C.) being necessary for the regeneration of the absorber. As a result, the use of the storage catalyst is only possible in motor vehicles that have a high exhaust gas temperature, d. H. especially in motor vehicles with a gasoline engine. However, the use is only partially possible here, since under certain operating conditions of the internal combustion engine, such as those given in city traffic, the acceleration phases high nitrogen oxide emissions occurs, but not a long-lasting high temperature is achieved for the regeneration of the absorber, especially of sulfur oxides, is required.

Aufgabe der Erfindung ist es, einen insbesondere für den Einsatz mit Dieselbrennkraftmaschinen bzw. direkteinspritzenden Otto-Motoren geeigneten Absorber für Stickoxide sowie ein entsprechendes Verfahren zur Verfügung zu stellen, mit denen auch bei niedrigen Abgastemperaturen ein Regenerieren des Absorbers möglich sein soll.The object of the invention is to provide a suitable for use with diesel engines or direct injection gasoline engines absorber for nitrogen oxides and a corresponding method available with which a regeneration of the absorber should be possible even at low exhaust gas temperatures.

Bei dem eingangs beschriebenen Absorber wird diese Aufgabe gelöst mit den kennzeichnenden Merkmalen des Anspruchs 1, hinsichtlich des Verfahrens wird die Aufgabe gelöst mit dem Verfahren gemäß Anspruch 21.In the absorber described above, this object is achieved with the characterizing features of claim 1, with regard to the method, the object is achieved with the method according to claim 21.

Die Unteransprüche zeigen bevorzugte Ausführungsformen, mit denen insbesondere auch bei sehr niedrigen Abgastemperaturen, wie sie beispielsweise bei direkteinspritzenden Verbrennungskraftmaschinen vorliegen, ein Regenerieren des Absorbers ermöglicht ist.The dependent claims show preferred embodiments with which, in particular, even at very low exhaust gas temperatures, as present for example in direct-injection internal combustion engines, a regeneration of the absorber is possible.

Erfindungsgemäß können die üblichen absorbierenden Materialien eingesetzt werden, wie sie beispielsweise in der US 4,755,499, aber auch in der EP 0 580 389 A oder WO 94-04258 beschrieben sind. All diesen Speichermaterialien ist gemeinsam, daß sie eine erhöhte Arbeitstemperatur haben, wobei insbesondere beim Regenerieren (insbesondere beim Entfernen der Schwefeloxide) eine noch höhere Temperatur erforderlich ist. Bei den meisten Speichermedien dieser Art werden Temperaturen im Bereich von 150°C bis 700 °C, insbesondere Temperaturen oberhalb 300 °C benötigt. Solche Temperaturen treten bei Kraftfahrzeugen mit Otto-Motoren üblicherweise auf, sind jedoch bei Dieselkraftfahrzeugen und insbesondere bei direkteinspritzenden Verbrennungskraftmaschinen verhältnismäßig selten.According to the invention, the usual absorbent materials can be used, as described, for example, in US Pat. No. 4,755,499, but also in EP 0 580 389 A or WO 94-04258. All these storage materials have in common that they have an elevated working temperature, in particular during regeneration (especially when removing the sulfur oxides) an even higher temperature is required. For most storage media of this type, temperatures in the range of 150 ° C to 700 ° C, especially temperatures above 300 ° C are needed. Such temperatures usually occur in motor vehicles with gasoline engines, but are relatively rare in diesel vehicles and especially in direct-injection internal combustion engines.

Die bevorzugten NOx-Speichermaterialien zeichnen sich also dadurch aus, daß sie unter nettooxidierenden Bedingungen (stöchiometrischer Überschuß an Oxidationsmitteln), wie sie im Abgas von Mager-Motoren vorliegen, Stickoxide zwischenspeichern und bei einer Verringerung des Sauerstoffüberschusses reduzieren können. Hierzu sind die NOx-Speicherkatalysatoren üblicherweise auch edelmetallbeschichtet, insbesondere mit den üblichen Edelmetallbeschichtungen für Dreiwegekatalysatoren. Die Regeneration des mit NOx beladenen Speichermaterials erfolgt dann vorteilhaft bei λ ≤ 1 in einer Regenerierphase.The preferred NOx storage materials are thus distinguished by the fact that they can store nitrogen oxides under net oxidizing conditions (stoichiometric excess of oxidizing agents), as present in the exhaust gas of lean-burn engines, and reduce them while reducing the oxygen excess. For this purpose, the NOx storage catalysts are usually also noble metal coated, in particular with the usual noble metal coatings for three-way catalysts. The regeneration of the NOx-laden storage material is then advantageously at λ ≤ 1 in a regeneration phase.

Üblicherweise laufen an den NOx-Speicherkatalysatoren verschiedene Reaktionen nacheinander bis gleichzeitig ab, wobei die wichtigsten Reaktionen

  • Oxidation des NO im Abgas zur NO2
  • Speicherung des NO2 als Nitrat
  • Zersetzung des Nitrats
  • Reduktion des zurückgebildeten NO2 zu Stickstoff und Sauerstoff
sind.Usually, various reactions take place successively or simultaneously at the NOx storage catalysts, with the most important reactions
  • Oxidation of the NO in the exhaust gas to NO 2
  • Storage of NO 2 as nitrate
  • Decomposition of the nitrate
  • Reduction of the reformed NO 2 to nitrogen and oxygen
are.

Wie oben beschrieben, ist der Verlauf der Reaktionen unter anderem abhängig von der Temperatur des Katalysators, aber auch von der Konzentration der Reaktionspartner am aktiven Zentrum des Katalysators und der Strömungsgeschwindigkeit des Gases.As described above, the course of the reactions depends inter alia on the temperature of the catalyst, but also on the concentration of the reactants at the active center of the catalyst and the flow rate of the gas.

Erfindungsgemäß hat es sich nun gezeigt, daß mit verschiedenen Faktoren, die miteinander kombinierbar sind, es auch mit nur geringem Aufwand möglich ist, die bekannten Abgasabsorber zu optimieren, so daß sie insbesondere für direkteinspritzende Verbrennungskraftmaschinen eingesetzt werden können. Die wesentlichen Merkmale sind hierbei:

  • Verringerung der Wandstärke des Trägerkörpers, auf dem die Absorptionsschicht aufgebracht ist, auf ≤ 160 µm, insbesondere ≤ 140 µm;
  • Verwendung von Metallträgern, vorteilhaft mit einer Wandstärke ≤ 50 µm, vorzugsweise ≤ 40 µm und insbesondere ≤ 30 µm; und/oder
  • Heizen des Absorbers auf eine Temperatur oberhalb der Temperatur des Abgasstromes.
According to the invention it has now been found that with various factors that can be combined with each other, it is also possible with little effort to optimize the known exhaust absorber, so that they can be used in particular for direct-injection internal combustion engines. The essential features are:
  • Reducing the wall thickness of the carrier body, on which the absorption layer is applied, to ≦ 160 μm, in particular ≦ 140 μm;
  • Use of metal supports, advantageously with a wall thickness ≤ 50 μm, preferably ≤ 40 μm and in particular ≤ 30 μm; and or
  • Heating the absorber to a temperature above the temperature of the exhaust stream.

Erfindungsgemäß hat es sich gezeigt, daß bei der Verwendung dünnwandiger keramischer Träger für die Absorptionsschicht, d. h. insbesondere von Trägerkörpern mit einer Wandstärke ≤ 0,14 mm, nicht nur ein schnellerer Temperaturanstieg der Absorptionsschicht möglich ist, sondern auch eine dickere Absorptionsschicht eingesetzt werden kann. Hierdurch wird zweierlei erreicht: zum einen können auch kurze Hochtemperaturphasen zum Regenerieren ausgenutzt werden, da die Speicherschicht schneller die höhere Temperatur annimmt, und zum anderen kann durch Auftragen einer dickeren Absorptionsschicht eine höhere Speicherkapazität erreicht werden, so daß über die längere Speicherfähigkeit des Absorbers beim Betrieb der Verbrennungskraftmaschine eine längere Zeitspanne verstreichen kann, bis der Speicher zu Regenerieren ist, so daß trotz der seltener auftretenden Temperaturspitzen im Abgasstrom von verbrauchsoptimierten Verbrennungskraftmaschinen kein Durchschlagen des Speichers (Erreichen der Sättigungsgrenze) erfolgt.According to the invention it has been shown that when using thin-walled ceramic support for the absorption layer, ie in particular of support bodies with a wall thickness ≤ 0.14 mm, not only a faster increase in temperature of the absorption layer is possible, but also a thicker absorption layer can be used. This achieves two things: on the one hand, even short high-temperature phases can be utilized for regeneration since the storage layer assumes the higher temperature more quickly and, on the other hand, a higher storage capacity can be achieved by applying a thicker absorption layer, so that over the longer storage capacity of the absorber during operation the internal combustion engine a longer Time can elapse until the memory is to regenerate, so that despite the more rarely occurring temperature peaks in the exhaust stream of consumption-optimized internal combustion engines, no breakthrough of the memory (reaching the saturation limit) takes place.

Erfindungsgemäß sind insbesondere Absorber mit einem Trägerkörper aus Metallfolie geeignet. Außerdem lassen sich bei der Verwendung eines Metallträgerkörpers die Kanäle, die mit der Absorptionsschicht beschichtet sind, unterschiedlich gestalten, so daß beispielsweise eine Verwirbelung (turbulente Strömung) des Abgasstromes in den Kanälen gezielt einstellbar ist.According to the invention absorbers are particularly suitable with a carrier body made of metal foil. In addition, when using a metal carrier body, the channels that are coated with the absorption layer, make different, so that, for example, a turbulence (turbulent flow) of the exhaust stream is selectively adjustable in the channels.

Besonders vorteilhaft werden erfindungsgemäß für den Absorber Trägerkörper mit unterschiedlichen Kanalabschnitten eingesetzt, wobei z. B. ein mittlerer Bereich der Kanäle zur Erzielung einer turbulenten Strömung verändert ist. Dies ist beispielsweise durch eine Veränderung des Kanalquerschnitts oder aber durch eine Verdrehung bzw. Verwindung der Kanäle möglich. Hierdurch läßt sich der Trägerkörper gezielt für besonders günstige Reaktionsbedingungen entlang der Strömungskanäle anpassen. Eine weitere Besonderheit des Trägerkörpers ist neben der möglichen unterschiedlichen Zahl an Kanälen in Strömungsrichtung und dem Einbringen von Querschnittsänderungen entlang der Strömungsrichtung auch das Segmentieren des Trägerkörpers, wobei z. B. ein Segment mit Absorptionsschicht nahe des Motorauslasses und ein weiteres Segment mit Absorptionsschicht etwas entfernter angeordnet wird. Hierdurch lassen sich auch bei unterschiedlichsten Fahrbedingungen auch bei verbrauchsoptimierten Motoren gute NOx-Reinigungswerte erzielen.Particularly advantageous according to the invention for the absorber carrier body with different channel sections are used, wherein z. B. a central region of the channels to achieve a turbulent flow is changed. This is possible, for example, by changing the channel cross-section or by twisting or twisting the channels. As a result, the carrier body can be adjusted specifically for particularly favorable reaction conditions along the flow channels. Another special feature of the carrier body is in addition to the possible different number of channels in the flow direction and the introduction of cross-sectional changes along the flow direction and the segmentation of the carrier body, wherein z. B. a segment with absorption layer near the motor outlet and another segment with absorption layer is arranged slightly more remote. As a result, good NOx cleaning values can be achieved even in fuel-optimized engines, even under very different driving conditions.

Erfindungsgemäß hat es sich gezeigt, daß der NOx-Speicher besonders gute Absorptions- und Desorptionseigenschaften hat, wenn die Strömungskanäle für das Abgas in einem mittleren Bereich zur Erzielung einer turbulenten Strömung verwirbelt sind, wohingegen der Einlaßbereich und der Auslaßbereich nicht diese eine turbulente Strömung besonders begünstigende Struktur haben. Als einfachstes Mittel zur Erzeugung einer solchen turbulenten Strömung ist beispielsweise ein Übergang von einem großen zu einem kleinen Durchmesser in den Kanälen, jedoch auch eine Verdrehung des gesamten Körpers in diesem Bereich ist geeignet zur Erzeugung der Turbulenzen. Die besonders günstigen Eigenschaften werden vermutlich durch eine Trennung der einzelnen Reaktionsschritte zur Stickoxidreduktion auf einzelne Segmente des Trägerkörpers erreicht, wobei der veränderte mittlere Bereich gegenüber dem unveränderten mittleren Bereich bessere Reaktionsbedingungen gewährleistet.According to the present invention, it has been found that the NO x storage has particularly good absorption and desorption characteristics when the flow passages for the exhaust gas are swirled in a central region to achieve a turbulent flow, whereas the inlet region and the outlet region do not particularly favor this turbulent flow Have structure. The simplest means of producing such a turbulent flow is, for example, a transition from a large to a small one Diameter in the channels, but also a rotation of the entire body in this area is suitable for generating the turbulence. The particularly favorable properties are presumably achieved by a separation of the individual reaction steps for the reduction of nitrogen oxides to individual segments of the carrier body, wherein the changed middle range guarantees better reaction conditions compared to the unchanged middle range.

Für die Erzielung besonders guter Umsätze hat die Absorptionsschicht eine vergrößerte Oberfläche von mindestens 20 m2/g, insbesondere mindestens 40 m2/g. Vorteilhaft hat die Absorptionsschicht vorzugsweise ein Porenvolumen von mindestens 0,2 cm3/g und insbesondere mindestens 0,4 cm3/g, wobei auch eine bimodale Porengrößenverteilung geeignet ist mit Mikroporen und Makroporen. Dies wird beispielsweise durch die Wahl einer bestimmten Partikelgröße für die Bildung der Absorberoberfläche erreicht, wobei auch Mischungen oder bestimmte Verteilungen unterschiedlicher Partikelgrößen geeignet sind.To achieve particularly good conversions, the absorption layer has an increased surface area of at least 20 m 2 / g, in particular at least 40 m 2 / g. Advantageously, the absorption layer preferably has a pore volume of at least 0.2 cm 3 / g and in particular at least 0.4 cm 3 / g, wherein a bimodal pore size distribution is also suitable with micropores and macropores. This is achieved, for example, by the choice of a specific particle size for the formation of the absorber surface, wherein mixtures or specific distributions of different particle sizes are also suitable.

Als Absorptionsoberfläche eignet sich insbesondere γ-Aluminiumoxid, das mit einem oder mehreren Elementen aus der Gruppe der Alkalimetalle, Erdalkalimetalle, seltenen Erden und/oder Lanthan beladen ist. Auch Kupfer und Mangan sind geeignete Elemente. Die Elemente liegen üblicherweise als Oxid, aber auch als Carbonat oder Nitrat vor, wobei die Speicherwirkung durch Bildung entsprechender Nitrate und Sulfate erzielt wird, die dann unter den entsprechenden Reaktionsbedingungen wieder zu Oxiden oder Carbonaten überführt werden. Hierdurch ist es möglich, NOx und/oder SOx insbesondere aus einem Abgas, das mindestens 1 % Sauerstoff enthält, zu absorbieren.The absorption surface is in particular γ-alumina, which is loaded with one or more elements from the group of alkali metals, alkaline earth metals, rare earths and / or lanthanum. Copper and manganese are also suitable elements. The elements are usually present as oxide, but also as carbonate or nitrate, wherein the storage effect is achieved by forming corresponding nitrates and sulfates, which are then converted under the appropriate reaction conditions again to oxides or carbonates. This makes it possible to absorb NOx and / or SOx in particular from an exhaust gas containing at least 1% oxygen.

Wie beschrieben, werden die absorbierten Stoffe insbesondere durch erhöhte Temperaturen und in reduzierender Atmosphäre wieder freigesetzt. Hierzu ist es vorteilhaft, wenn im Abgas die Sauerstoffkonzentration ermittelt wird, wobei dann die Sauerstoffkonzentration oder eine mit der Sauerstoffkonzentration in bekannter Beziehung stehende Größe zur Steuerung des Absorptions- bzw. Desorptionsvorganges herangezogen werden kann. Entsprechendes gilt auch für die Temperatur des Abgasstroms, wobei entscheidend die Temperatur der Absorptionsschicht ist, die unmittelbar oder mittelbar bestimmt wird. So kann die Temperatur beispielsweise durch Messung der Temperatur des Abgasstroms bzw. des Trägerkörpers gemessen werden; auch eine Temperaturbestimmung über ein Kennfeld der Verbrennungskraftmaschine ist möglich.As described, the absorbed substances are released in particular by increased temperatures and in a reducing atmosphere. For this purpose, it is advantageous if the oxygen concentration is determined in the exhaust gas, in which case the oxygen concentration or a quantity in known relationship with the oxygen concentration can be used to control the absorption or desorption process. The same applies to the temperature of the exhaust gas stream, wherein the temperature of the absorption layer is decisive, which is determined directly or indirectly. Thus, the temperature can be measured for example by measuring the temperature of the exhaust stream or the carrier body; It is also possible to determine the temperature via a characteristic map of the internal combustion engine.

Mit der vorliegenden Erfindung lassen sich Absorptionsschichten in einer Dicke von mindestens 50 µm, insbesondere mindestens 70 µm und besonders vorteilhaft mindestens 90 µm herstellen (durchschnittliche Schichtdicke eines Querschnitts; Werte gelten für Keramik, bei Metall gelten die halben Werte) wobei sich diese Schichtdicke der Absorptionsschicht über vorzugsweise mindestens 50 % und insbesondere mindestens 80 % des Absorbers erstreckt. Solche Schichtdicken ermöglichen gegenüber den herkömmlichen Absorbern eine höhere Speicherkapazität und damit die oben beschriebenen längeren Intervalle bis zur Regeneration.With the present invention it is possible to produce absorption layers in a thickness of at least 50 μm, in particular at least 70 μm and particularly advantageously at least 90 μm (average layer thickness of a cross section, values apply to ceramics, in the case of metal the half values apply), whereby this layer thickness of the absorption layer preferably over at least 50% and in particular at least 80% of the absorber extends. Such layer thicknesses allow a higher storage capacity compared with the conventional absorbers and thus the longer intervals described above until regeneration.

Gemäß dem mit zur Erfindung gehörenden Verfahren kann das Regenerieren vorteilhaft dann erfolgen, wenn die Betriebsbedingungen der Verbrennungskraftmaschine eine entsprechend hohe Temperatur des Abgasstroms und damit der Absorptionsschicht bewirken. Erfindungsgemäß ist jedoch eine Zusatzheizung der Absorptionsschicht vorgesehen, die über die Gemischbildung erfolgt. Bevorzugte Beheizungsmaßnahmen sind Zündungsmaßnahmen, Veränderung des λ, Absenken des λ auf < 1 und Senkundärluftzugabe zum Erzeugen von Exothermie an einem Oxidationskatalysator bzw. über eine Zündeinrichtung. Besonders vorteilhaft ist hierbei wieder ein segmentierter Absorber, der dann reaktionsspezifisch beheizt wird. So kann beispielsweise nur ein stromabwärts angeordneter Absorberbereich beheizt werden, insbesondere bei einer deutlichen räumlichen Trennung der Absorbersegmente (siehe oben).. Durch die Anordnung einzelner Segmente für Einzelreaktionen in unterschiedlichem Abstand zum Auslaßventil in motornaher und motorferner Position läßt sich außerdem eine thermische Alterung des Absorbers vermindern (neben dem Vorteil der besonders günstigen Reaktionstemperaturen in einzelnen Absorberbereichen).According to the method associated with the invention, the regeneration can advantageously take place when the operating conditions of the internal combustion engine cause a correspondingly high temperature of the exhaust gas stream and thus of the absorption layer. According to the invention, however, an additional heating of the absorption layer is provided, which takes place via the mixture formation. Preferred heating measures are ignition measures, changing the λ, lowering the λ to <1 and Senkundärluftzugabe for generating exothermic oxidation of an oxidation catalyst or via an ignition device. Particularly advantageous here again is a segmented absorber, which is then heated reaction-specific. Thus, for example, only a downstream arranged absorber area can be heated, especially with a significant spatial separation of Absorbersegmente (see above) .. By the arrangement of individual segments for individual reactions at different distances to the exhaust valve in the engine and motor remote position can also be a thermal aging of the absorber reduce (in addition to the advantage of particularly favorable reaction temperatures in individual absorber areas).

Da für die Freisetzung und Umsetzung des NOx aus dem Speicher und die Freisetzung der Schwefeloxide aus dem Speicher unterschiedliche Temperaturen notwendig sind (beim letzteren höhere), kann außerdem so verfahren werden, daß eine Desorption der Schwefeloxide (die insbesondere als Sulfat vorliegen) in größeren Zeitspannen bzw. bei Bedarf vorgenommen wird, so daß der Speicher nur gelegentlich auf die hohen Temperaturen erhitzt wird, die für eine Desorption der Schwefeloxide notwendig sind. Auch hierdurch wird einer frühzeitigen Alterung des Speichers entgegengewirkt, so daß eine besonders gute Langzeitstabilität des Absorbers erreicht wird. Im übrigen bedient sich das Verfahren der oben bei dem Absorber und im Ausführungsbeispiel beschriebenen Maßnahmen, wie auch die beim Verfahren und im Ausführungsbeispiel beschriebenen Merkmale bei dem eingangs beschriebenen Absorber eingesetzt werden können.Since different temperatures are required for the release and conversion of the NOx from the storage tank and the release of the sulfur oxides from the storage tank (higher in the latter case), it is also possible to carry out a desorption of the Sulfur oxides (which are present in particular as sulfate) is carried out in longer periods or on demand, so that the memory is only occasionally heated to the high temperatures that are necessary for a desorption of the sulfur oxides. This also counteracts premature aging of the reservoir, so that a particularly good long-term stability of the absorber is achieved. Moreover, the method uses the measures described above in the absorber and in the embodiment, as well as the features described in the method and in the embodiment can be used in the absorber described above.

Die Erfindung wird im folgenden anhand eines Ausführungsbeispiels und einer Zeichnung näher beschrieben.The invention will be described in more detail below with reference to an embodiment and a drawing.

Die Zeichnung zeigt den Absorber in einem Abgassystem einer Brennkraftmaschine (Ottomotor).The drawing shows the absorber in an exhaust system of an internal combustion engine (gasoline engine).

Ein Absorber 1 sitzt in einem Abgasstrang 2 einer fremdgezündeten Verbrennungskraftmaschine 3 mit direkter Kraftstoffeinspritzung, deren Betrieb über ein Motormanagement gesteuert wird. Das Motormanagement 4 wirkt hierzu auf eine Einspritzpumpe 5, die Kraftstoff von einem (nicht dargestellten) Tank 6 zu einer Einspritzdüse 7 fördert. Außerdem erfolgt über das Motormanagement 4 über die Zündkerze 18 auch die Zündung des Kraftstoff-Luftgemisches im Zylinder (wobei die Zündspule nicht dargestellt ist). Übersichtshalber sind die verschiedensten zu dem Motormanagement 4 führenden üblichen Zu- und Ableitungen nicht dargestellt.An absorber 1 is seated in an exhaust line 2 of a spark-ignited internal combustion engine 3 with direct fuel injection, whose operation is controlled by an engine management system. For this purpose, the engine management 4 acts on an injection pump 5, which conveys fuel from a tank 6 (not shown) to an injection nozzle 7. In addition, via the engine management 4 via the spark plug 18 and the ignition of the fuel-air mixture in the cylinder (wherein the ignition coil is not shown). For the sake of clarity, the most diverse leading to the engine management 4 common supply and discharge lines are not shown.

In dem Abgasstrang 2 ist ferner noch ein Dreiwegekatalysator 8 stromabwärts von dem Absorber 1 angeordnet, auch eine Anordnung des Dreiwegekatalysators 8 stromaufwärts des Absorbers 1 ist möglich.In addition, a three-way catalyst 8 is arranged downstream of the absorber 1 in the exhaust line 2, and an arrangement of the three-way catalyst 8 upstream of the absorber 1 is also possible.

Der Absorber 1 ist aus zwei Metallfolien aufgebaut, von denen die eine gewellt mit einer glatten Folie verbunden (an den Wellenbergen verlötet) ist. Durch Zusammenrollen dieser mehrlagigen Folie erhält man einen zylindrischen Körper mit einer Vielzahl von sich in ihm axial erstreckenden Kanälen. Ferner wurde der Trägerkörper des Absorbers in einem mittleren Bereich 15 um seine Längsachse gedreht, so daß hier die einzelnen Kanäle 16 verengt und gewunden sind. Eine ähnlich wirkende Turbulenzen bildende Struktur läßt sich auch mit einer Querwellung in einer oder beiden der Metallfolien erreichen.The absorber 1 is composed of two metal foils, one of which is corrugated with a smooth foil (soldered to the wave crests). By rolling this multilayer film to obtain a cylindrical body having a plurality of axially extending channels in it. Furthermore, the carrier body of the absorber was rotated in a central region 15 about its longitudinal axis, so that here the individual channels 16th narrowed and tortuous. A similarly acting turbulence-forming structure can also be achieved with a transverse undulation in one or both of the metal foils.

Die Metallfolie enthält wenige Prozent Aluminium und wird anoxidiert, damit ein γ-aluminiumoxidhaltiger washcoat besser auf der Metallfolie haftet. Der Aluminiumoxidwashcoat enthält ferner die Elemente Natrium, Barium, Cer und Lanthan, die als Salze (Nitrate, Oxide, Hydrooxide) auf das Aluminiumoxid aufgezogen sind. Durch Tränken des gewickelten Trägerkörpers mit dem washcoat und anschließendes Brennen erhält man den Absorber. Zusätzlich wird der Absorber mit einer platin- und rhodiumhaltigen Lösung (zusätzlich oder anstatt des Rhodiums kann die Lösung auch Palladium enthalten) getränkt, aus der dann die entsprechenden Edelmetalle als solche freigesetzt werden. Diese Edelmetallbeschichtung entspricht einer Dreiwegekatalysator-Beschichtung. Der so erhaltene Absorber wird elektrisch kontaktiert und so in ein Gehäuse eingesetzt, daß ein Stromfluß durch ihn gegen Masse (das Gehäuse) möglich ist. Die elektrische Kontaktierung 9 ist anderenends mit der Steuerung 4 verbunden. Außerdem ist in den Trägerkörper noch ein Temperaturfühler 10 eingesetzt, der ebenfalls zu der Steuerung 4 führt.The metal foil contains a few percent of aluminum and is oxidized so that a washcoat containing γ-aluminum oxide adheres better to the metal foil. The Aluminiumoxidwashcoat also contains the elements sodium, barium, cerium and lanthanum, which are grown as salts (nitrates, oxides, hydroxides) on the alumina. By impregnating the wound carrier body with the washcoat and then firing, the absorber is obtained. In addition, the absorber is impregnated with a platinum and rhodium-containing solution (in addition to or instead of rhodium, the solution may also contain palladium), from which then the corresponding precious metals are released as such. This noble metal coating corresponds to a three-way catalyst coating. The absorber thus obtained is electrically contacted and inserted into a housing so that a current flow through it to ground (the housing) is possible. The electrical contact 9 is connected at the other end to the controller 4. In addition, a temperature sensor 10 is used in the carrier body, which also leads to the controller 4.

Stromaufwärts von dem Absorber 1 ist eine Breitbandlambdasonde 11 in das Abgasrohr eingesetzt, die wiederum ihre der im Abgasstrom vorliegenden Sauerstoffkonzentration proportionalen Werte an die Steuerung 4 weitergibt. Außerdem ist stromaufwärts der Lambdasonde 11 eine Kraftstoffeinspritzung 12 vorgesehen, die entsprechend von Steuerbefehlen aus der Steuerung 4 mit Kraftstoff versorgt wird. Zwischen dem Absorber 1 und dem nachgeschalteten Katalysator 8 ist eine Lufteindüsung 13 vorgesehen, die Luft von einer von der Steuerung 4 gesteuerten Pumpe 14 erhält.Upstream of the absorber 1, a broadband lambda probe 11 is inserted into the exhaust pipe, which in turn passes on its values proportional to the oxygen concentration present in the exhaust gas flow to the controller 4. In addition, a fuel injection 12 is provided upstream of the lambda probe 11, which is supplied in accordance with control commands from the controller 4 with fuel. Between the absorber 1 and the downstream catalytic converter 8, an air injector 13 is provided which receives air from a pump 14 controlled by the controller 4.

Die Verbrennungskraftmaschine 3 ist vom Typ eines direkteinspritzenden Ottomotors, dessen Abgasstrom normalerweise einen hohen Sauerstoffüberschuß und eine Temperatur um 200 °C bis 500 °C hat.The internal combustion engine 3 is of a direct injection gasoline engine type whose exhaust gas flow normally has a high oxygen excess and a temperature around 200 ° C to 500 ° C.

Im Betrieb der Brennkraftmaschine werden im Abgas vorhandene Stickoxide und Oxide des Schwefels in der Absorptionsschicht des Absorbers 1 eingelagert, wobei gleichzeitig eventuell vorhandene oxidierbare Bestandteile (meist Kohlenwasserstoffe) durch die Edelmetallbeschichtung des Absorbers 1 oxidiert werden. Bei Erreichen der Sättigungsgrenze oder aber in vorbestimmten Zeitintervallen (auch andere Steuerungsgrößen sind möglich, wie beispielsweise eine NOx-Bestimmung im Abgas nach dem Absorber) ist der Absorber zu regenerieren d. h. von dem beispielsweise als Bariumnitrat eingelagerten NOx zu befreien. Gleichzeitig können hierbei auch (beispielsweise als Bariumsulfat) eingelagerte Oxide des Schwefels entfernt werden. Hierzu wird von dem Steuergerät 4 über den Temperaturfühler 10 geprüft, ob die Temperatur der Absorberbeschichtung für ein Regenerieren hoch genug ist. Sofern die Temperatur unter 500 °C liegt, wird über die Kraftstoffeindüsung 12 in den Abgasstrom Kraftstoff eingedüst, der mit dem im Abgasstrom vorhandenen Sauerstoff katalytisch an der Edelmetallbeschichtung des Absorbers 1 verbrennt, wodurch sich dessen Temperatur erhöht.During operation of the internal combustion engine, nitrogen oxides present in the exhaust gas and oxides of sulfur are incorporated in the absorption layer of the absorber 1, with any oxidizable constituents (usually hydrocarbons) being oxidized at the same time by the noble metal coating of the absorber 1. Upon reaching the saturation limit or at predetermined time intervals (and others Control variables are possible, such as a NOx determination in the exhaust gas after the absorber) is the absorber to regenerate ie to free from the embedded example as barium nitrate NOx. At the same time (for example as barium sulfate) embedded oxides of sulfur can be removed in this case. For this purpose, it is checked by the control unit 4 via the temperature sensor 10, whether the temperature of the absorber coating for a regeneration is high enough. If the temperature is below 500 ° C, fuel is injected via the fuel injection 12 into the exhaust gas stream, which catalytically burns with the oxygen present in the exhaust gas stream at the noble metal coating of the absorber 1, thereby increasing its temperature.

Sobald der Absorber 1 genügen erhitzt ist, wird ein fettes Gemisch im Abgas eingestellt, d. h. weiterhin Kraftstoff (über 12) eingedüst und/oder durch Einspritzen eines fetten Gemisches in den Zylinder. Hierbei wird vorteilhaft im Ansaugkanal 16 der Brennkraftmaschine 3 eine Drossel 17 über die Steuerung 4 geschlossen, so daß weniger Luft in die Verbrennungskraftmaschine 3 gelangt. Hierdurch reduziert sich der Sauerstoffanteil im Abgasstrom derart, daß das NOx und SOx aus der Absorptionsschicht freigegeben und das NOx auch gleich reduziert wird. Das Ende des Regenerierens kann zeitgesteuert ablaufen aber auch beispielsweise über die Exothermie der Reaktionstemperatur kontrolliert werden. In einer weiteren Ausgestaltung kann das Regenerieren, wie in der DE 43 42 062 A beschrieben, erfolgen, d. h. der Abgasstrom wird vor dem Absorber gedrosselt und insbesondere in einen Bypaß zum Absorber geführt.Once the absorber 1 is heated enough, a rich mixture is set in the exhaust, d. H. continue to inject fuel (over 12) and / or by injecting a rich mixture into the cylinder. Here, a throttle 17 is advantageously closed via the controller 4 in the intake passage 16 of the internal combustion engine 3, so that less air enters the internal combustion engine 3. This reduces the proportion of oxygen in the exhaust gas flow in such a way that the NOx and SOx are released from the absorption layer and the NOx is also reduced immediately. The end of the regeneration can be time-controlled but can also be controlled, for example, via the exothermic nature of the reaction temperature. In a further embodiment, the regeneration, as described in DE 43 42 062 A, take place, d. H. the exhaust gas stream is throttled before the absorber and in particular passed into a bypass to the absorber.

Um eventuell noch vorhandene Kohlenwasserstoffe abzubauen, ist nach dem Absorber 1 die Lufteindüsung 13 vorgesehen, die während der Kraftstoffeindüsung (über 12) oder des Betreibens der Brennkraftmaschine mit einem fetten Gemisch von der Steuerung 4 in Betrieb gesetzt wird. Hierdurch werden eventuell noch vorhandene Kohlenwasserstoffe in dem nachgeschalteten Katalysator 8 zu Kohlendioxid und Wasser oxidiert.In order to reduce hydrocarbons that may still be present, after the absorber 1, the Lufteindüsung 13 is provided, which is set during the fuel injection (about 12) or the operation of the internal combustion engine with a rich mixture of the controller 4 in operation. As a result, any remaining hydrocarbons are oxidized in the downstream catalyst 8 to carbon dioxide and water.

Gewünschtenfalls kann die Kraftstoffeindüsung 12 entfallen, da über die Kraftstoffeinspritzung 7 in den Brennraum der Brennkraftmaschine ohne Schwierigkeiten eine genügende Anfettung des Abgasstromes erreicht werden kann.If desired, the fuel injection 12 can be dispensed with, since a sufficient enrichment of the exhaust gas flow can be achieved without difficulty via the fuel injection 7 into the combustion chamber of the internal combustion engine.

Da beim Regenerieren die Leistung der Brennkraftmaschine 3 vermindert sein kann, können Maßnahmen vorgesehen werden, daß bei einem völligen Durchtreten des Gasstellmittels für die Brennkraftmaschine das Regenerieren zumindest für einen gewissen Zeitraum unterdrückt wird.Since the power of the internal combustion engine 3 can be reduced during regeneration, measures can be taken to ensure that regeneration is suppressed at least for a certain period of time when the gas actuating means for the internal combustion engine completely passes through.

Claims (27)

  1. Spark-ignition internal combustion engine or diesel internal combustion engine having an exhaust section in which there is arranged an absorber (1) having a support body, to which an absorption layer with an increased surface area around which an exhaust-gas stream can flow is applied, which absorption layer is suitable for reversible absorption of at least one nitrogen oxide (NOx) and/or at least one sulphur oxide (SOx), and a control unit (4), which controls the regeneration of the absorber by setting certain parameters of the exhaust-gas stream, characterized in that in order to heat the absorber (1) to a temperature which is suitable for its regeneration, there is additional heating for the absorption layer by means of the mixture formation in the exhaust gas.
  2. Internal combustion engine according to Claim 1, characterized in that a metallic support body is provided, the metal being a metal sheet or a metal foil.
  3. Internal combustion engine according to Claim 2, characterized in that the support body has a wall thickness of ≤ 0.1 mm, in particular ≤ 0.05 mm.
  4. Internal combustion engine according to Claim 1, characterized in that a ceramic support body with a wall thickness of < 0.14 mm is provided.
  5. Internal combustion engine according to one of the preceding claims, characterized in that the enlarged surface area amounts to at least 20 m2/g, in particular at least 40 m2/g and particularly advantageously at least 100 m2/g, based on the mass of the absorption layer which can be reached by the gas stream.
  6. Internal combustion engine according to one of the preceding claims, characterized in that the absorption layer contains an aluminium oxide, in particular γ-aluminium oxide.
  7. Internal combustion engine according to one of the preceding claims, characterized in that the absorption layer contains an element selected from the group consisting of the alkali metals, alkaline-earth metals, rare earths, lanthanum, titanium, copper and/or manganese.
  8. Internal combustion engine according to Claim 7, characterized in that the absorption layer contains at least one of the elements barium, sodium, potassium.
  9. Internal combustion engine according to one of the preceding claims, characterized in that the absorption layer absorbs NOx and/or SOx from an exhaust gas from an internal combustion engine (3) which is operated under lean-burn mode with an excess of oxygen.
  10. Internal combustion engine according to one of the preceding claims, characterized in that the absorption layer releases NOx and/or SOx in a reducing atmosphere and/or when there is a low oxygen concentration.
  11. Internal combustion engine according to Claim 9 and/or 10, characterized in that an oxygen concentration-determining device, which determines the oxygen concentration or a variable which includes the oxygen concentration, is provided, which device transmits the oxygen concentration or the variable including this concentration as an input variable to the control unit, which initiates loading or unloading of the absorber (1).
  12. Internal combustion engine according to one of the preceding claims, characterized in that the absorption layer releases NOx and/or SOx at an elevated temperature.
  13. Internal combustion engine according to Claim 12, characterized by a temperature-determining device (10), which determines the temperature, or a variable which includes the temperature, of the gas stream and/or of the absorption layer and/or of the support body and transmits the temperature or the variable which includes the temperature as an input variable to the control unit (4), which initiates loading or unloading of the absorber (1).
  14. Internal combustion engine according to Claims 12 and 13, characterized in that the control unit (4) has as input variables the oxygen concentration and the temperature or the variables which include them.
  15. Internal combustion engine according to one of the preceding claims, characterized in that the absorption layer has a thickness of at least 50 µm in ceramics and at least 25 µm on a metal support.
  16. Internal combustion engine according to one of the preceding claims, characterized in that the absorption layer is in the washcoat.
  17. Internal combustion engine according to one of the preceding claims, characterized in that the absorption layer bears at least one precious metal.
  18. Internal combustion engine according to Claim 17, characterized in that the absorption layer forms an oxidation catalyst or a three-way catalyst with the precious metal.
  19. Internal combustion engine according to one of the preceding claims, characterized in that the absorption layer has a pore volume of at least 0.2 cm3/g, based on the mass which the gas stream is able to flow to.
  20. Internal combustion engine according to one of the preceding claims, characterized in that an oxidation catalytic converter, in particular a three-way catalytic converter (8) as an independent unit is connected upstream and/or downstream of the absorber (1) .
  21. Method for controlling an absorber (1) arranged in an exhaust section of a spark-ignition internal combustion engine or a diesel internal combustion engine (3), comprising the steps of:
    - operating the internal combustion engine (3) so as to form an oxygen-containing exhaust-gas stream;
    - guiding the oxygen-containing exhaust-gas stream over an absorption layer for NOx;
    - storing the NOx in the absorption layer;
    - heating the absorption layer at least to a predetermined temperature by means of additional heating by means of the mixture formation in the exhaust gas while the internal combustion engine (3) is operating, before, at the same time as or after
    - forming a low-oxygen exhaust-gas stream or an exhaust-gas stream with a stoichiometric excess of reducing agent;
    - desorbing the NOx from the absorption layer, with the NOx being reduced in the low-oxygen exhaust-gas stream or in the exhaust-gas stream with a stoichiometric excess of reducing agent while the absorption layer is at least at the predetermined temperature;
    - forming an oxygen-containing exhaust-gas stream again;
    - ending the heating of the absorption layer to the predetermined temperature, before, at the same time as or after the above step; and
    - repeating the steps from: - storing the NOx in the absorption layer.
  22. Method according to Claim 21, characterized in that the heating of the absorption layer by means of additional heating is achieved by an injection of fuel into the exhaust-gas stream and catalytic combustion thereof, ignition measures and/or a change in the λ value.
  23. Method according to Claim 21 or 22, characterized in that before the step of:
    - heating the absorption layer at least to a predetermined temperature by means of additional heating by means of mixture formation while the internal combustion engine (3) is operating, before, at the same time as or after
    a step of:
    - determining whether the absorption layer and/or an item whose temperature is related to that of the absorption layer is at least at the predetermined temperature,
    is carried out, and in that the steps of:
    - heating the absorption layer at least to a predetermined temperature by means of additional heating by means of the mixture formation during operation of the internal combustion engine (3), before, at the same time as or after
    - ending the heating of the absorber (1) to the predetermined temperature, before, at the same time as or after the above steps; and
    are dispensed with, if, during the determination step, it is detected that the absorption layer and/or the item whose temperature is related to that of the absorption layer is at least at the predetermined temperature.
  24. Method according to one of Claims 21 to 23, characterized in that in addition to NOx, at least one sulphur oxide (SOx) is also stored by and desorbed from the absorber (1) during the method steps.
  25. Method according to one of Claims 21 to 24, characterized in that the desorption takes place as a function of time and/or of the loading of the absorption layer.
  26. Method according to one of Claims 21 to 25, characterized in that the absorption layer contains γ-aluminium oxide and at least one element selected from the group consisting of the alkali metals, alkaline-earth metals, rare earths and/or lanthanum.
  27. Method according to one of Claims 21 to 26, characterized in that the exhaust-gas stream is guided over a support body which bears the absorption layer and has a multiplicity of passages (16) running in parallel.
EP03008344A 1996-08-19 1997-08-07 Spark-ignited internal combustion engine with an NOx-adsorber Expired - Lifetime EP1342496B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE19633049 1996-08-19
DE19633049 1996-08-19
EP97941920A EP0944424B1 (en) 1996-08-19 1997-08-07 SPARK-IGNITED INTERNAL COMBUSTION ENGINE WITH AN NOx-ADSORBER

Related Parent Applications (2)

Application Number Title Priority Date Filing Date
EP97941920A Division EP0944424B1 (en) 1996-08-19 1997-08-07 SPARK-IGNITED INTERNAL COMBUSTION ENGINE WITH AN NOx-ADSORBER
EP97941920.7 Division 1998-02-26

Publications (3)

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EP1342496A2 EP1342496A2 (en) 2003-09-10
EP1342496A3 EP1342496A3 (en) 2003-09-24
EP1342496B1 true EP1342496B1 (en) 2007-05-23

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EP97941920A Expired - Lifetime EP0944424B1 (en) 1996-08-19 1997-08-07 SPARK-IGNITED INTERNAL COMBUSTION ENGINE WITH AN NOx-ADSORBER
EP03008344A Expired - Lifetime EP1342496B1 (en) 1996-08-19 1997-08-07 Spark-ignited internal combustion engine with an NOx-adsorber

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US (2) US6808686B1 (en)
EP (2) EP0944424B1 (en)
JP (1) JP2000516681A (en)
KR (1) KR100524503B1 (en)
DE (2) DE59712848D1 (en)
WO (1) WO1998007497A1 (en)

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19816276C2 (en) 1998-04-11 2000-05-18 Audi Ag Method and device for operating an internal combustion engine
DE10047809B4 (en) * 2000-09-27 2014-01-09 Volkswagen Ag Method for operating control of a secondary air pump and emission control system with a secondary air pump
JP2003065042A (en) * 2001-08-30 2003-03-05 Toyota Motor Corp Exhaust emission control device for internal combustion engine
JP2005193171A (en) * 2004-01-08 2005-07-21 Ict:Kk Exhaust emission control device of internal combustion engine
JP4413020B2 (en) * 2004-01-21 2010-02-10 ヤンマー株式会社 Exhaust gas purification device and control method thereof
BRPI0508845A (en) * 2004-03-15 2007-08-28 Honeywell Int Inc method for removing a sulfur-containing compound from a fuel stream of an internal combustion engine, removal fuel filter, and system for extending time between regeneration cycles of an emission control device
DE102004021370A1 (en) 2004-04-30 2005-11-17 Robert Bosch Gmbh Method and device for operating a hybrid vehicle
DE102005026036A1 (en) * 2005-06-03 2006-12-07 Emitec Gesellschaft Für Emissionstechnologie Mbh Method and device for providing ammonia in an exhaust gas stream of an internal combustion engine
US7563423B2 (en) * 2006-12-22 2009-07-21 Alstom Technology Ltd Method and apparatus for catalyst regeneration
JP4877123B2 (en) * 2007-07-23 2012-02-15 マツダ株式会社 Engine exhaust purification system
DE102007044937B4 (en) 2007-09-20 2010-03-25 Continental Automotive Gmbh Method and device for operating an internal combustion engine
JP6111948B2 (en) * 2013-09-19 2017-04-12 トヨタ自動車株式会社 Exhaust gas purification device for internal combustion engine
US10081241B2 (en) 2015-12-10 2018-09-25 Curtis Alan Roys Diesel fuel guard
CN109404100B (en) * 2018-11-09 2020-11-20 潍柴动力股份有限公司 Exhaust purification device, exhaust purification control method and control system thereof
US11242785B2 (en) 2020-06-30 2022-02-08 Saudi Arabian Oil Company Process to capture SOx onboard vehicles and ships
DE102021105722A1 (en) 2021-03-10 2022-09-15 Volkswagen Aktiengesellschaft Internal combustion engine with catalytic converter device with different specific amounts of catalytic converter material
US20220371223A1 (en) * 2021-05-24 2022-11-24 The Marketer's Engineering Tool Source LLC Low-dust cutting device for multiple tiles and low-dust scoring device for concrete masonry units

Family Cites Families (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4755499A (en) 1984-10-12 1988-07-05 Noxso Corporation Sorbent for removing nitrogen oxides, sulfur oxides and hydrogen sulfide from gas streams
US4849274A (en) 1987-06-19 1989-07-18 W. R. Grace & Co.-Conn. Honeycomb fluid conduit
US5296198A (en) * 1990-11-09 1994-03-22 Ngk Insulators, Ltd. Heater and catalytic converter
CZ283018B6 (en) 1991-02-01 1997-12-17 Merck Sharp And Dohme Limited Imidazole, triazole and tetrazole derivatives, process of their preparation, their use and pharmaceuticals based thereon
US5240682A (en) 1991-05-06 1993-08-31 W. R. Grace & Co.-Conn Reinforced corrugated thin metal foil strip useful in a catalytic converter core, a catalytic converter core containing said strip and an electrically heatable catalytic converter containing said core
JP2783074B2 (en) * 1991-10-29 1998-08-06 トヨタ自動車株式会社 Exhaust gas purification device for internal combustion engine
JP2605586B2 (en) 1992-07-24 1997-04-30 トヨタ自動車株式会社 Exhaust gas purification device for internal combustion engine
DE4226394C2 (en) * 1992-08-10 1999-01-21 Degussa Process for catalytic exhaust gas cleaning with improved cold start behavior
US5362463A (en) 1992-08-26 1994-11-08 University Of De Process for removing NOx from combustion zone gases by adsorption
JP2605556B2 (en) * 1992-10-13 1997-04-30 トヨタ自動車株式会社 Exhaust gas purification device for internal combustion engine
DE69307822T2 (en) * 1992-10-20 1997-08-21 Corning Inc Process for converting exhaust gases and device with thermally stable zeolites
US5406790A (en) 1992-12-11 1995-04-18 Toyota Jidosha Kabushiki Kaisha Exhaust gas purification device for an engine
JP2830669B2 (en) 1992-12-29 1998-12-02 トヨタ自動車株式会社 Exhaust gas purification device for internal combustion engine
DE4339025C2 (en) * 1992-12-14 1997-08-07 Mannesmann Ag Device for cleaning polluted exhaust air
JP3116628B2 (en) * 1993-01-21 2000-12-11 株式会社日本自動車部品総合研究所 Suction device
DE4319294C1 (en) * 1993-06-10 1994-05-19 Daimler Benz Ag Denitrification of engine exhaust gas without adding reducing agent - by adsorption in adsorber in exhaust pipe, periodic desorption with hot gas and recirculation to combustion in suction air supply
US5451558A (en) * 1994-02-04 1995-09-19 Goal Line Environmental Technologies Process for the reaction and absorption of gaseous air pollutants, apparatus therefor and method of making the same
US5633217A (en) 1994-09-12 1997-05-27 Corning Incorporated Method of making a high strength catalyst, catalyst support or adsorber
JP3358766B2 (en) 1994-12-16 2002-12-24 トヨタ自動車株式会社 Exhaust gas purification catalyst
FR2728300B1 (en) * 1994-12-19 1997-03-14 Peugeot EXHAUST GAS TREATMENT DEVICE OF A COMPRESSION IGNITION ENGINE INCLUDING A CATALYST AND A NITROGEN OXIDE ADSORBER PLACED IN THE EXHAUST MANIFOLD
EP0944428B1 (en) * 1996-08-19 2013-06-26 Volkswagen Aktiengesellschaft Method for operating an internal combustion engine with a NOx adsorber

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Publication number Publication date
KR20000068019A (en) 2000-11-25
EP1342496A2 (en) 2003-09-10
US6808686B1 (en) 2004-10-26
US20010004450A1 (en) 2001-06-21
DE59712848D1 (en) 2007-07-05
EP0944424B1 (en) 2003-07-16
DE59710447D1 (en) 2003-08-21
EP0944424A1 (en) 1999-09-29
US6759020B2 (en) 2004-07-06
EP1342496A3 (en) 2003-09-24
WO1998007497A1 (en) 1998-02-26
JP2000516681A (en) 2000-12-12
KR100524503B1 (en) 2005-10-31

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